Conventional solid electrolytic capacitors contain an anode body, dielectric layer, and a solid electrolyte. An anode wire projects from a surface of the capacitor for electrically connecting the anode body to a termination. One beneficial technique that is sometimes employed to connect the anode wire to the termination is laser welding. Lasers generally contain resonators that include a laser medium capable of releasing photons by stimulated emission and an energy source that excites the elements of the laser medium. The energy source may provide continuous energy to the laser medium to emit a continuous laser beam or energy discharges to emit a pulsed laser beam. One type of suitable laser is one in which the laser medium consists of an aluminum and yttrium garnet (YAG), doped with neodymium (Nd) and the excited particles are neodymium ions Nd3+. Such lasers typically emit light at a wavelength of about 1064 nanometers in the infrared spectrum. Unfortunately, problems are often experienced when attempting to laser weld capacitors for small case sizes. Namely, the small case size requires that the laser be positioned relatively close to the location of the anode wire and termination. At such a close location, however, the laser can be readily deflected by the wire or anode termination and come into contact with the solid electrolyte of the capacitor. Due to its high energy, the deflected laser beam can significantly increase the temperature of the solid electrolyte to a point where it begins to carbonize. The carbonized portions of the solid electrolyte come into a contact with a dielectric layer and may thus lead to poor electrical properties (e.g., high leakage current) in the resulting capacitor.
As such, a need exists for solid electrolytic capacitors that can be laser welded and yet retain excellent properties.